Sigma has been looking into whether its EF lenses play nicely on Canon’s R System of mirrorless cameras, specifically the R5, and the company has just reported its findings. While modern Sigma lenses generally play nicely with the R line, there are a few caveats customers may want to be aware of.
“We have verified the operation with our SIGMA GLOBAL VISION (SGV) interchangeable lenses (Contemporary, Art, and Sports lines) for Canon EF mounts used on the ‘Canon EOS R5‘ with Canon’s mount adapter ‘EF-EOS R Series‘, and confirmed that there were no problems with general operations such as AE, AF, and image stabilization,” Sigma says.
But there are 6 things Sigma does want customers to know:
#1. Update Firmware of Older Global Vision Lenses
“For SGV interchangeable lenses released before 2017 , it is necessary that the lens firmware is updated to Ver.2.00 or later. The release year can be confirmed by the edition number (A017, C015, etc.) engraved on the lens barrel.”
#2. Turn On the Camera’s Lens Corrections
“After setting the Digital Lens Optimizer to [OFF], set the ‘Peripheral Illumination Correction’, ‘Chromatic Aberration Correction’, and ‘Distortion Correction’ of the ‘Lens Aberration Correction’ function to [ON] to achieve the appropriate corrections in accordance with the optical characteristics of each lens.”
#3. Know Where AF Can Be Used
“AF can be used within the area of approximately 80% of the height and 80% of the width of the sensor surface.”
#4. Turn ‘Full-time MF’ Off for In-Camera Stabilization
“For lenses without an OS (Optical Stabilizer) mechanism, the in-camera image stabilization can not be used when the Full-time MF setting is set to ‘Full-time MF ON’ via SIGMA Optimization Pro. When using in-camera image stabilization, please set the Full-time MF setting to ‘Full-time MF OFF’. The default Full-time MF setting is ‘Full-time MF OFF’.”
#5. Turn Off In-Camera IS for Non-Global Vision Lenses
“Image stabilization does not work optimally with interchangeable lenses which are not from the Contemporary, Art or Sports line. Please turn off the camera’s Image stabilization setting, or turn off the OS switch for lenses equipped with an OS (Optical Stabilizer) mechanism when using.”
#6. Manual Focus Recommended for Non-Global Vision Lenses
“For interchangeable lenses which are not from the Contemporary, Art or Sports lines, using MF is recommended, since it may be difficult to achieve sufficient focusing speed and accuracy when AF is used.”
Aside from these issues, though, you should feel comfortable switching over from EF to RF and adapting your existing Sigma EF lenses with a Canon EF-EOS R adapter.